PATHOGENESIS OF ALS IN SOD1 TRANSGENIC MICE

本项目的{长期目标}是调查 ALS的发病机制使用作为动物模型的转基因小鼠， 表达突变的胞质超氧化物歧化酶（SOD），并开发马达 神经元疾病 突变启动运动神经元的机制 死亡没有很好的定义（目前正在调查的一个假设 突变分子的异常折叠 过氧化物与活性通道中的还原铜相互作用，从而 成为过氧化反应的底物。 该反应 在关键目标上产生有毒的羟基加合物。 我们将通过分析对细胞的影响来检验这种过氧化假设。 在ALS小鼠的疾病表型的措施，将减少 过氧化氢的过氧化作用。 具体目标（1）是生成 具有突变SOD1转基因和不同的 谷胱甘肽过氧化物酶水平（从没有到高于正常水平10倍）。 这些实验将确定是否加速清除 过氧化氢可改善病程。 第1102章针对性（二） 如果可以的话，将测试绑定和屏蔽的可能性 铜在mutuant活性位点将减少氢的进入 过氧化氢对这种金属，从而减缓疾病。 铜螯合剂 可以尝试的药物包括青霉胺和二乙基二硫代氨基甲酸酯。 小鼠将 监测发病时间和总生存期， 和这些干预措施。 我们还将监测电生理 量化运动单位功能和活动水平的参数， 脑和脊髓中谷胱甘肽过氧化物酶和{过氧化氢酶}。 我们 我相信这些实验将是重要的，因为它们将测试 这两个关于神经毒性机制的具体假设 突变的SOD 1和潜在的治疗策略在这种致命的疾病。

The {long term objective} of this project is to investigate the pathogenesis of ALS using as an animal model transgenic mice which over- express mutant cytosolic superoxide dismutase (SOD) and develop motor neuron disease. The mechanisms whereby mutations initiate motor neuron death are not well defined {One hypothesis currently under investigation is that} abnormal folding of the mutant molecule allows hydrogen peroxide to interact with reduced copper in the active channel, thereby becoming a substrate for a peroxidation reaction. This reaction generates toxic hydroxyl adducts on critical targets. We will test this peroxidation hypothesis by analyzing the effects on the disease phenotype in ALS mice of measures which will reduce peroxidation of hydrogen peroxide. Specific Aim (1) is to generate doubly transgenic mice with both the mutant SOD1 transgene and varying levels of glutathione peroxidase (from none to 10-fold above normal). These experiments will determine whether accelerated clearance of hydrogen peroxide can ameliorate the disease course. Specific Aim (2) will test the possibility that binding and shielding if accessible copper in the mutuant active site will reduce access of hydrogen peroxide to this metal and thereby slow the disease. Copper chelators to be tried include penicillamine and diethyldithiocarbamate. Mice will be monitored for timing of onset of illness and overall survival without and with these interventions. We will also monitor electrophysiological parameters that quantitate motor unit function and activity levels of glutahione peroxidase and {catalase} in brain and spinal cord. We believe these experiments will be significant because they will test both a specific hypothesis regarding the mechanism of neurotoxicity of mutant SOD1 and a potential therapeutic strategy in this lethal disease.